GB 4706.12-1995 Special requirements for safe storage-type electric water heaters for household and similar electrical appliances
Some standard content:
National Standard of the People's Republic of China
Safety of household and similar electrical appliances
Special requirements for storage water heaters
Safety of household and similar electrical appliancesParticular requirements for storage water heatersGB 4706.12-- 1995
IEC335-2-21--1989
replaces GB4706.12-86
This standard is equivalent to IEC335-2-21 (1989) "Safety of household and similar electrical appliances Part 2: Special Requirements for Storage Electric Water Heaters" and its supplements to No. 1 (1990), No. 2 (1990) and No. 3 (1992). This standard should be used in conjunction with GB4706.1-92 "General safety requirements for household and similar electrical appliances". The parts of this standard that say "applicable" mean that the corresponding provisions in GB4706.1-92 are applicable to this standard; the parts of this standard that say "replace" should be subject to the provisions of this standard; this standard The part marked "added" means that in addition to the corresponding provisions of GB4706.1--92, it must also comply with the added provisions of this standard. 1Scope
GB4706.1--92. Chapter 1 is applicable except for the following content. 1.1 This article is replaced by the following content:
This standard applies to fixed storage-type electric water heaters that heat water below the boiling point (hereinafter referred to as water heaters). Note: ① The water heaters referred to in this standard may be water heaters with an insulation layer for long-term storage of hot water, or water heaters without insulation layers for short-term storage of hot water. ② Water heaters that are not intended for general household use, but are still dangerous when used in public places. Water heaters are within the scope of this standard. For example: water heaters used in shops, light industry sectors, and farms.
③ This standard does not consider the special hazards present in nurseries and places where unattended activities for the elderly, the sick, and the disabled occur. When using water heaters in these places, additional requirements are required.
④ Water heaters used in cars, boats or airplanes generally have additional requirements. ③ Water heaters used in tropical areas generally require special requirements. It should also comply with the relevant requirements stipulated by the national health department and labor protection department. This standard does not apply to:
water heaters designed for industrial use; - in corrosive or explosive atmospheres (dust, steam) or flammable gas); instant electric water heater.
2 Terminology
This chapter in GB4706.1-92 is applicable except for the following. 2.2.29 This article is replaced by the following:
Full heat dissipation conditions refer to the working state of the water heater when it is installed for normal use and is initially filled with cold water. The following article is added to this chapter: ||tt| |storagewaterheater
2.2.101 Water-type water heater
refers to a fixed appliance that heats water in a container. It can store hot water for a long time or temporarily, and is equipped with a device to control or limit the water temperature. The State Bureau of Technical Supervision approved the implementation on 1996-10-01 on December 13, 1996 | A water heater that works under pressure has one or more valves at the water outlet system to control the flow of water. See Figures 1-la and 1-Ib
2.2.103 Sink-fed water heater refers to a cistern-fed water heater. A water heater that supplies water from an independent sink. The outflow of hot water is controlled by one or more valves at the water outlet system of the water heater. It has a vent to the atmosphere to allow the rising water to return to the sink. See Figure 1-1.
2.2.104 Tank-type water heater cistern-type water heater refers to a sink-type water heater that is integrated with a water supply tank. See Figure 1-1.
2.2.105 The open-outlet waterheater refers to a water heater that uses a valve on the side of the water inlet pipe to control the flow of water in the water heater. The rising water overflows through the outlet pipe. See Figure 1-N.
2.2.106 Vented water heater refers to a water heater that is connected to the atmosphere. At any time, the pressure on the water surface is the same as the atmospheric pressure. See Figure 1-V.
2.2.107 Rated pressure refers to the water pressure of the water heater calibrated by the manufacturer. Note: For closed water heaters and tank-supplied water heaters, the rated pressure refers to the maximum normal pressure of the water supply system connected to the water heater. Water outlet
3 General requirements
Closed water heater
[Water outlet
Water tank water heater
Ib
GB4706.12-1995
Water outlet
Outlet diffused water heater
Figure 1 Classification of storage water heaters according to working conditions The contents of this chapter in GB4706.1-92 are applicable. 4 General instructions in testing
This chapter in GB4706.1-92 is applicable except for the following content. 4.2 The following content is added to this article:
The tests of Articles 22.101 and 22.104 can be conducted on a separate container or heat exchanger. 4.3 This article is replaced by the following:
water regime water heater
open water heater
water inlet
Except for 24.103 and 24.104, it is the same as 22.101 and 22.104 in Article 19 Except for the test before the test in Chapter 19, unless the test is performed on a separate container or heat exchanger and is unlikely to be affected by the test in Chapter 19, all other tests should be performed in the order of GB4706.1--92. Note: Before starting the test, in order to check whether it is in normal working condition, the water heater should work at rated voltage. 4.4 The following content is added to this article:
GB4706.12-1995
Water heaters designed to be used in more than one installation position shall be tested at the most unfavorable position specified in the installation instructions. 4.5 This article adds the following content:
It is stipulated that water heaters supplied with cold water shall be supplied directly by tap water. 5 Ratings
This chapter in GB4706.1-92 is applicable except for the following content. This chapter adds the following clauses:
5.101 Rated pressure
Minimum rated pressure of closed water heater, 0.6MPa; sink water heater, 0.2MPa;
Tank-type water heater, 0MPa;
Outlet diffused water heater, 0MPa;
Open water heater, oMPa.
Determine whether it is qualified by inspecting the mark. Note: Although the rated pressure of outlet-spread water heaters and open-type water heaters is 0MPa, for safety, these water heaters still need to withstand the pressure test of Article 22.101.
6 Classification
This chapter in GB4706.1--92 is applicable except for the following content. 6.1 Added:
According to working conditions, it is divided into:
closed water heater;
sink water heater;
one-tank water heater;
export Dispersed water heater;
One-opening water heater.
Note: Water heaters can have different types of components according to their different working conditions. 7 Mark
This chapter in GB4706.1-92 is applicable except for the following content. 7.1 The following content is added to this article:
Water heaters should be marked with rated pressure in \Pa" or "bar". Open-type water heaters and outlet-spread water heaters should be marked with 0Pa. outlet-spread water heaters must be marked in The following is permanently marked near the outlet connection: WARNING: This outlet is for water discharge and must not be connected to any branch pipe or fitting, except as recommended by the manufacturer. NOTE: Splash-proof water heaters must be marked with the splash-proof construction symbol. 7.8 This article is replaced by the following:
When the water heater has more than two power supply wires connected, a fixed connection diagram should be provided on the appliance, unless the wiring method is obvious. For water heaters with multiple power supplies, the terminals or leads of each circuit must have clear and easily identifiable signs near them, unless the water heater already has a wiring diagram.
Note: A multi-power water heater refers to a water heater that contains one or more electric heating elements connected through a clock-controlled switch or meter. 7.12 The following content is added to this article:
In the instruction manual of the outlet-type water heater, it should be specified that the outlet serves the purpose of venting to the atmosphere. This outlet must not be connected to any faucet or fitting not specified by the manufacturer.
The instruction manual of the closed water heater should point out: GB 4706.12--1995
—If water is discharged from the discharge pipe of the pressure relief device, what measures should be taken; the discharge pipe should be kept open to the atmosphere ;
How to drain a water heater.
The installation instructions for closed water heaters should indicate that the discharge pipe connected to the pressure relief device should be installed with a downward slope. 7.14 The following content is added to this article:
Thermal circuit breakers equipped with replaceable parts should be marked with the operating temperature. This mark can be seen after the thermal circuit breaker is installed and the electrical components are removed if necessary. This mark shall be clearly visible behind the cover but without removing any independent insulation layer. The following clauses are added to this chapter:
7.101 The water inlet and outlet should be clearly marked, and these marks should not be marked on replaceable parts. If colors are used for marking, blue represents the cold water inlet and red represents the hot water outlet. Compliance is determined by inspection.
Note: Arrows can also be used to indicate the direction of water flow at the water outlet and water inlet. 8 Protection against electric shock
The contents of this chapter in GB4706.1-92 are applicable. 9 Start-up of electric appliances
The contents of this chapter in GB4706.1--92 are applicable. 10Input power and current
The contents of this chapter in GB4706.1--92 are applicable. 11 Fever
This chapter in GB4706.1-92 is applicable except for the following content. 11.7 This article is replaced by the following:
The water heater operates until it is in a stable state and until the temperature limiter operates or the thermostat cuts off the current for the first time after 16 hours, choose the shortest test time.
11.8 The "ordinary wood" item in the continuation of Table 3 of this article is replaced by the following: Ordinary wood 65℃
Test the wall, top plate, and bottom plate of the corner:
With insulation Water heaters on the first floor are 60℃ | 12.1 This article is replaced by the following:
The design and structure of the water heater should be considered to withstand the overload that may occur during normal use. Compliance is determined by the test specified in Article 12.2. Subsequently, except for open-type water heaters, the test of Article 12.101 is immediately carried out. For water heaters with pressure switches, compliance is determined by the test of Article 12.3. 12.2 Paragraph 4 of this article is replaced with the following: The water heater shall be subjected to 4 cycles under sufficient heat release conditions in accordance with the provisions of 11.7, and the working time and cooling time shall be separated (cooling time GB4706.12-1995
(8h), before each working time, the water heater should be replaced with cold water. The following content is added to this article:
During the first drainage after each working period, the water temperature is measured by a thermocouple installed at the outlet pipe, except when the distance between the end of the water pipe and the top of the container exceeds the height of the container When the temperature is 1/6, the thermocouple should be placed at the geometric center of the upper 1/6 of the container to measure the water temperature.
The water temperature shall not exceed 98℃.
The following clauses are added to this chapter:
12.101 In addition to open-type water heaters, other types of water heaters must adjust the power supply voltage so that the input power is 1.27 times the rated input power and run for at least 12 hours.
After this cycle, starting from when the thermostat cuts off the current for the first time, slowly pour cold water into the container at a flow rate of about 2L per minute, or at a rate equivalent to 10 times the rated volume of the container per minute. % of the water volume is poured into the container until the thermostat is turned on again. When the thermostat cuts off the current for the second time, cold water is injected at the same flow rate until the thermostat is turned on again, and this is repeated until a stable state is reached.
Measure the water temperature at the water outlet through a thermocouple placed in the water outlet pipe. The temperature shall not exceed 98°C. 13 Electrical insulation and leakage current at operating temperature The contents of this chapter in GB4706.1-92 are applicable. 14 Suppression of radio and television interference
The contents of this chapter in GB4706.1-92 are applicable. 15 Waterproof
This chapter in GB4706.1-92 is applicable except for the following content. 15.3 The following content is added to this article:
For open water heaters, after closing the water outlet, conduct an overflow test. Except for open-type water heaters, other water heaters are not subject to this test. 16 Insulation resistance and electrical strength
The contents of this chapter in GB4706.1-92 are applicable. 17 Overload protection
The contents of this chapter in GB4706.1-92 are applicable. 18 Durability
The contents of this chapter in GB4706.1--92 are applicable. 19 Abnormal operation
This chapter in GB4706.1--92 is applicable except for the following content. 19.1 This article is replaced by the following:
Electrical appliances should be designed to avoid fire, mechanical accidents or electric shock accidents due to abnormal work or misoperation. Except for sink-type water heaters and water tank-type water heaters, Other water heaters shall be qualified according to the tests of 19.2, 19.3 and 19.4, except those with the following three characteristics:
has a metal shell;
has a non-combustible insulation layer; ||tt| |GB4706.12-1995
The ratio of the rated input power to the container volume shall not be greater than 2kW/10L. Water heaters other than sink-fed water heaters and tank-type water heaters that have the three characteristics specified above shall be qualified by the test of Article 19.101, except for water heaters that cannot be easily drained during normal use. In any test, if the non-self-resetting thermal circuit breaker operates, the heating element is damaged, or if the current is disconnected for other reasons before reaching steady state, the heating cycle is considered to be over, but if the current is disconnected due to the heating element or If the damage is caused by man-made weak parts, the relevant test should be repeated on a second sample. This sample should also meet the various conditions specified in Article 19.11. Article 19.11 applies to all electrical appliances.
Note: ① If the electric heating element or artificially weak parts of the second sample are damaged, the sample itself should not be regarded as unqualified. ② Artificially weak components are components designed to fail under abnormal operating conditions to prevent unsafe situations within the scope of this standard. Such components can be replaceable components, such as a resistor, a capacitor or a thermal Fuses, or parts that can replace components, such as an impossible-to-reach and non-resettable thermal circuit breaker installed on the motor. ③Sink-fed water heaters, tank-type water heaters and water heaters with the above four characteristics but which are difficult to drain during normal use are not subject to the test of this chapter.
④ If a one-way valve, pipe interceptor or air spacer is used to prevent the water heater from emptying through the water inlet pipe, whether the above device is installed in the water heater or is required to be installed by the instructions, such a water heater cannot be considered to be in use. A water heater that is easily drained in normal use shall not be considered in normal use if it is drained only through a hole opened for maintenance purposes. 19.2 The following content is added to this article:
The water heater shall be installed in accordance with the provisions of Chapter 11, and shall be connected in series with a fuse one grade larger than the rated current of the water heater. When operating in the drained state, the thermostat operating during the tests of Chapter 11 should be short-circuited. Note: If the water heater is equipped with more than one thermostat, and these thermostats are in operation during the test of Chapter 11, they shall be short-circuited in turn. 19.4 This article is replaced by the following:
For outlet-type water heaters and open-type water heaters, the test of 19.2 must be repeated, but there should be water in the container, and the water level should be at least 10mm higher than the highest point of the electric heating element. , the test is conducted under sufficient heat dissipation conditions and a voltage of 1.27 times the rated input power is input until the steady state is determined.
Note: If the water heater is damaged during the above test, use a new specimen. The following clauses are added to this chapter:
19.101 According to the provisions of Article 19.2, when the water heater is operated in the empty state for 24 hours, the power supply voltage should be such that the input power is 1 of the rated input power.27 times.
Note: During the test, the thermostat and thermal circuit breaker are allowed to operate. 20 Stability and mechanical hazards
The contents of this chapter in GB4706.1-92 are applicable. 21 Mechanical strength
The contents of this chapter in GB4706.1-92 are applicable. 22 Structure
This chapter in GB4706.1-92 is applicable except for the following content. The following content is added to this chapter:
Water heaters should be at least drip-proof.
22.1 This article is replaced by the following:
The water heater has an electrical structure of Class I, Class I and Class H. Compliance is determined by inspection and relevant tests. 22.3 Add the following content to this article:
GB4706.12—1995
Note: If the device for fixing the water heater can be adjusted to an angle not exceeding 5° from the normal use position, or within this position range If the temperature can be adjusted to a suitable temperature using a thermostat, this test will not be performed. 22.7 This article is replaced by the following:
Enclosed water heaters must be equipped with a thermal circuit breaker. The action of the thermal circuit breaker should be through a switch that is separate from the adjustment function of the thermal controller to ensure that the water heater is fully disconnected from the power supply. .
For direct heating closed water heaters, the thermal circuit breaker should not be reset without opening the non-removable cover. Compliance is determined by inspection.
22.11 The following content is added to this article:
During normal use, if condensation water may accumulate in the water heater, the shell must have a diameter of at least 5mm or a width of at least 3mm and an area of ??20mm2 Drain holes to drain water away from damaging electrical insulation. Compliance is determined by measurement.
22.24 This article adds the following content:
For internal wiring, thermal insulation cannot be used as basic insulation. The following clause is added to this chapter:
22.101 Water heaters must be able to withstand the water pressure generated during normal use. During the test, the water pressure rises to the following specified value at a rate of 0.13MPa/s and is maintained for 5 minutes. Check whether the container and heat exchanger (if any) are qualified.
The prescribed value of water pressure is:
- twice the rated water pressure for a pair of closed water heaters; - 0.3MPa for a water tank water heater; - 0.15 for an outlet diffused water heater MPa; a pair of open water heaters is 0.03MPa.
After the test, there should be no water leakage, and the container and heat exchanger should not have permanent deformation that affects safety. Note: ① Water heaters, containers and heat exchangers equipped with heat exchangers shall withstand pressure tests according to the classification of relevant components. ②For open-type water heaters, the test is only conducted when there is doubt. ③This test can be carried out on a separate container. 22.102 Safety (Pressure relief devices, whether incorporated in the water heater or provided separately, must maintain a pressure within the container not greater than 0.1 MPa above its rated pressure.
Safety is achieved by subjecting the container to a slowly increasing pressure and observing The pressure at which the device operates is used to determine whether it is qualified. 22.103 The water outlet system of the outlet-type water heater must be unobstructed and shall not cause the pressure of the container to exceed the rated pressure. The structure of the open-type water heater should have a diameter of at least 5mm or a width of at least 3mm. , a hole with an area of ??20mm2 that is connected to the atmosphere.
Determine whether it is qualified by visual inspection and measurement. Note: If the area of ??the water outlet of the water heater from the heated part is equal to or larger than the area of ??the water inlet entering the heated part. , the first requirement is met.
22.104 The outlet-type water heater must be able to withstand the vacuum shock occurring in normal use, and the container is evacuated to a vacuum of 33kPa without holes. and keep it for 15 minutes. Qualification shall be determined by testing.
After the test, the container should not have any deformation that affects safety. Note: ① If there is a vacuum safety relief valve, the test can be performed. It is carried out on a separate container. 22.105 The water inlet pipe that can transport the water in the container from the top of the container to the bottom of the container should be clamped with reliable tools so that its displacement in all directions in the horizontal plane does not exceed 6mm. GB4706.12-1995.
In addition, if the water inlet pipe is made of non-metallic material, it should be able to withstand dissolution and brittleness within the normal use temperature range of the water heater, and be able to prevent deformation, breakage, bending and similar situations
Pass inspection. Compliance is determined by inspection. 22.106 Components that are in direct contact with the outer surface of the container should be reliably fixed to prevent loosening during normal use.
22.107 For embedded components without shells. For installed water heaters, if a metal mesh is used to fix the insulation material, it should be reliably fixed in place so that the creepage distance and electrical resistance should not be compromised due to sliding and twisting during installation, transportation and use. The gap is reduced to the minimum allowable value specified in Article 29.1. Compliance shall be determined by inspection and measurement. 22.108 The water heater shall be connected to the water supply pipe in a reliable manner and must have a reliable device. 22.109 For water heaters that cannot be drained through the drainage device in the water pipe and have a capacity greater than 15L, there should be a drain valve or a water heater. The drain plug can be opened only with tools, so that the water in the water heater can be easily drained. Check whether it is qualified by visual inspection and manual testing. Note: ① After the water in the electric water heater is drained, there will be residue below the water source valve. A small amount of water is allowed. ② The drain valve or drain plug can be installed in the safety valve of the electric water heater to prevent the water heater from being damaged due to freezing. 23 Internal wiring
GB4706.1-92. The contents of this chapter are applicable. 24 Components
This chapter in GB4706.1--92 is applicable except for the following content. 24.1 The following content is added to this article:
Note: The switch installed in the water heater does not need to be operated frequently. The following clauses are added to this chapter:
24.101 Thermal circuit breakers shall be of the non-automatic reset type. They shall have an automatic breaking mechanism or be positioned within a non-removable cover that can be reset only after the cover is moved.
Conformity is determined by inspection.
Note: ① "Automatic circuit breaking" means that when the water temperature in the water heater exceeds the specified limit, the thermal circuit breaker should be structured to open the contacts regardless of the position of the starting device.
② The thermal circuit breaker can be used if the contact automatically returns to the closed position if the reset device is kept in the reset position when the water becomes cold. 24.102 The operating temperature of the thermal circuit breaker in a closed water heater should not exceed the following recommended values: 99C; 130C140C.
Compliance is determined by inspection and Clause 24.103 or 24.104. During the test, install the water heater according to normal usage conditions, fill the container with water, and close the water outlet valve.
24.103 For temperatures of 130°C and 140°C, all thermostats used in the tests of Chapter 11 shall be short-circuited. When the water heater works until the thermal circuit breaker operates, use a thermocouple to measure the maximum temperature reached by the container; for non-metallic containers, use a thermocouple to measure the water temperature in the container.
For metal containers, fix the thermocouple on the outer surface of the upper dome. If the container is placed vertically, fix the thermocouple at half the height of the dome; if the container is placed horizontally, attach two thermocouples As shown in Figure 2-1, it is fixed on the outer surface along the maximum height line of the container.
For non-metallic containers, place the thermocouple 50mm below the upper inner surface of the container, and the lead wire of the thermocouple passes through the outlet water7. Replace this article with the following:
Closed water heaters must be equipped with a thermal circuit breaker. The action of the thermal circuit breaker should be through a switch that is separate from the adjustment function of the thermal controller to ensure that the water heater is fully disconnected from the power supply. .
For direct heating closed water heaters, the thermal circuit breaker should not be reset without opening the non-removable cover. Compliance is determined by inspection.
22.11 The following content is added to this article:
During normal use, if condensation water may accumulate in the water heater, the shell must have a diameter of at least 5mm or a width of at least 3mm and an area of ??20mm2 Drain holes to drain away water to prevent damage to electrical insulation. Compliance is determined by measurement.
22.24 This article adds the following content:
For internal wiring, thermal insulation cannot be used as basic insulation. The following clause is added to this chapter:
22.101 Water heaters must be able to withstand the water pressure generated during normal use. During the test, the water pressure rises to the following specified value at a rate of 0.13MPa/s and is maintained for 5 minutes. Check whether the container and heat exchanger (if any) are qualified.
The prescribed value of water pressure is:
- twice the rated water pressure for a pair of closed water heaters; - 0.3MPa for a water tank water heater; - 0.15 for an outlet diffused water heater MPa; a pair of open water heaters is 0.03MPa.
After the test, there should be no water leakage, and the container and heat exchanger should not have permanent deformation that affects safety. Note: ① Water heaters, containers and heat exchangers equipped with heat exchangers shall withstand pressure tests according to the classification of relevant components. ②For open-type water heaters, the test is only conducted when there is doubt. ③This test can be carried out on a separate container. 22.102 Safety (Pressure relief devices, whether incorporated in the water heater or provided separately, must maintain a pressure within the container not greater than 0.1 MPa above its rated pressure.
Safety is achieved by subjecting the container to a slowly increasing pressure and observing The pressure at which the device operates is used to determine whether it is qualified. 22.103 The water outlet system of the outlet-type water heater must be unobstructed and shall not cause the pressure of the container to exceed the rated pressure. The structure of the open-type water heater should have a diameter of at least 5mm or a width of at least 3mm. , a hole with an area of ??20mm2 that is connected to the atmosphere.
Determine whether it is qualified by visual inspection and measurement. Note: If the area of ??the water outlet of the water heater from the heated part is equal to or larger than the area of ??the water inlet entering the heated part. , the first requirement is met.
22.104 The outlet-type water heater must be able to withstand the vacuum shock occurring in normal use, and the container is evacuated to a vacuum of 33kPa without holes. and keep it for 15 minutes. Qualification shall be determined by testing.
After the test, the container should not have any deformation that affects safety. Note: ① If there is a vacuum safety relief valve, the test can be performed. It is carried out on a separate container. 22.105 The water inlet pipe that can transport the water in the container from the top of the container to the bottom of the container should be clamped with reliable tools so that its displacement in all directions in the horizontal plane does not exceed 6mm. GB4706.12-1995.
In addition, if the water inlet pipe is made of non-metallic material, it should be able to withstand dissolution and brittleness within the normal use temperature range of the water heater, and be able to prevent deformation, breakage, bending and similar situations
Pass inspection. Compliance is determined by inspection. 22.106 Components that are in direct contact with the outer surface of the container should be reliably fixed to prevent loosening during normal use.
22.107 For embedded components without shells. For installed water heaters, if a metal mesh is used to fix the insulation material, it should be reliably fixed in place so that the creepage distance and electrical resistance should not be compromised due to sliding and twisting during installation, transportation and use. The gap is reduced to the minimum allowable value specified in Article 29.1. Compliance shall be determined by inspection and measurement. 22.108 The water heater shall be connected to the water supply pipe in a reliable manner and must have a reliable device. 22.109 For water heaters that cannot be drained through the drainage device in the water pipe and have a capacity greater than 15L, there should be a drain valve or a water heater. The drain plug can be opened only with tools, so that the water in the water heater can be easily drained. Check whether it is qualified by visual inspection and manual testing. Note: ① After the water in the electric water heater is drained, there will be residue below the water source valve. A small amount of water is allowed. ② The drain valve or drain plug can be installed in the safety valve of the electric water heater to prevent the water heater from being damaged due to freezing. 23 Internal wiring
GB4706.1-92. The contents of this chapter are applicable. 24 Components
This chapter in GB4706.1--92 is applicable except for the following content. 24.1 The following content is added to this article:
Note: The switch installed in the water heater does not need to be operated frequently. The following clauses are added to this chapter:
24.101 Thermal circuit breakers shall be of the non-automatic reset type. They shall have an automatic breaking mechanism or be positioned within a non-removable cover that can be reset only after the cover is moved.
Conformity is determined by inspection.
Note: ① "Automatic circuit breaking" means that when the water temperature in the water heater exceeds the specified limit, the thermal circuit breaker should be structured to open the contacts regardless of the position of the starting device.
②Thermal circuit breaker can be used if the contact automatically returns to the closed position if the reset device is kept in the reset position when the water becomes cold. 24.102 The operating temperature of the thermal circuit breaker in a closed water heater should not exceed the following recommended values: 99C; 130C140C.
Compliance is determined by inspection and Clause 24.103 or 24.104. During the test, install the water heater according to normal usage conditions, fill the container with water, and close the water outlet valve.
24.103 For temperatures of 130°C and 140°C, all thermostats used in the tests of Chapter 11 shall be short-circuited. When the water heater works until the thermal circuit breaker operates, use a thermocouple to measure the maximum temperature reached by the container; for non-metallic containers, use a thermocouple to measure the water temperature in the container.
For metal containers, fix the thermocouple on the outer surface of the upper dome. If the container is placed vertically, fix the thermocouple at half the height of the dome; if the container is placed horizontally, attach two thermocouples As shown in Figure 2-1, it is fixed on the outer surface along the maximum height line of the container.
For non-metallic containers, place the thermocouple 50mm below the upper inner surface of the container, and the lead wire of the thermocouple passes through the outlet water7. Replace this article with the following:
Closed water heaters must be equipped with a thermal circuit breaker. The action of the thermal circuit breaker should be through a switch that is separate from the adjustment function of the thermal controller to ensure that the water heater is fully disconnected from the power supply. .
For direct heating closed water heaters, the thermal circuit breaker should not be reset without opening the non-removable cover. Compliance is determined by inspection.
22.11 The following content is added to this article:
During normal use, if condensation water may accumulate in the water heater, the shell must have a diameter of at least 5mm or a width of at least 3mm and an area of ??20mm2 Drain holes to drain away water to prevent damage to electrical insulation. Compliance is determined by measurement.
22.24 This article adds the following content:
For internal wiring, thermal insulation cannot be used as basic insulation. The following clause is added to this chapter:
22.101 Water heaters must be able to withstand the water pressure generated during normal use. During the test, the water pressure rises to the following specified value at a rate of 0.13MPa/s and is maintained for 5 minutes. Check whether the container and heat exchanger (if any) are qualified.
The prescribed value of water pressure is:
- twice the rated water pressure for a pair of closed water heaters; - 0.3MPa for a water tank water heater; - 0.15 for an outlet diffused water heater MPa; a pair of open water heaters is 0.03MPa.
After the test, there should be no water leakage, and the container and heat exchanger should not have permanent deformation that affects safety. Note: ① Water heaters, containers and heat exchangers equipped with heat exchangers shall withstand pressure tests according to the classification of relevant components. ②For open-type water heaters, the test is only conducted when there is doubt. ③This test can be carried out on a separate container. 22.102 Safety (Pressure relief devices, whether incorporated in the water heater or provided separately, must maintain a pressure within the container not greater than 0.1 MPa above its rated pressure.
Safety is achieved by subjecting the container to a slowly increasing pressure and observing The pressure at which the device operates is used to determine whether it is qualified. 22.103 The water outlet system of the outlet-type water heater must be unobstructed and shall not cause the pressure of the container to exceed the rated pressure. The structure of the open-type water heater should have a diameter of at least 5mm or a width of at least 3mm. , a hole with an area of ??20mm2 that is connected to the atmosphere.
Determine whether it is qualified by visual inspection and measurement. Note: If the area of ??the water outlet of the water heater from the heated part is equal to or larger than the area of ??the water inlet entering the heated part. , the first requirement is met. bzxZ.net
22.104 The outlet-type water heater must be able to withstand the vacuum shock occurring in normal use, and the container is evacuated to a vacuum of 33kPa without holes. and keep it for 15 minutes. Qualification shall be determined by testing.
After the test, the container should not have any deformation that affects safety. Note: ① If there is a vacuum safety relief valve, the test can be performed. It is carried out on a separate container. 22.105 The water inlet pipe that can transport the water in the container from the top of the container to the bottom of the container should be clamped with reliable tools so that its displacement in all directions in the horizontal plane does not exceed 6mm. GB4706.12-1995.
In addition, if the water inlet pipe is made of non-metallic material, it should be able to withstand dissolution and brittleness within the normal use temperature range of the water heater, and be able to prevent deformation, breakage, bending and similar situations
Pass inspection. Compliance is determined by inspection. 22.106 Components that are in direct contact with the outer surface of the container should be reliably fixed to prevent loosening during normal use.
22.107 For embedded components without shells. For installed water heaters, if a metal mesh is used to fix the insulation material, it should be reliably fixed in place so that the creepage distance and electrical resistance should not be compromised due to sliding and twisting during installation, transportation and use. The gap is reduced to the minimum allowable value specified in Article 29.1. Compliance shall be determined by inspection and measurement. 22.108 The water heater shall be connected to the water supply pipe in a reliable manner and must have a reliable device. 22.109 For water heaters that cannot be drained through the drainage device in the water pipe and have a capacity greater than 15L, there should be a drain valve or a water heater. The drain plug can be opened only with tools, so that the water in the water heater can be easily drained. Check whether it is qualified by visual inspection and manual testing. Note: ① After the water in the electric water heater is drained, there will be residue below the water source valve. A small amount of water is allowed. ② The drain valve or drain plug can be installed in the safety valve of the electric water heater to prevent the water heater from being damaged due to freezing. 23 Internal wiring
GB4706.1-92. The contents of this chapter are applicable. 24 Components
This chapter in GB4706.1--92 is applicable except for the following content. 24.1 The following content is added to this article:
Note: The switch installed in the water heater does not need to be operated frequently. The following clauses are added to this chapter:
24.101 Thermal circuit breakers shall be of the non-automatic reset type. They shall have an automatic breaking mechanism or be positioned within a non-removable cover that can be reset only after the cover is moved.
Conformity is determined by inspection.
Note: ① "Automatic circuit breaking" means that when the water temperature in the water heater exceeds the specified limit, the thermal circuit breaker should be structured to open the contacts regardless of the position of the starting device.
② The thermal circuit breaker can be used if the contact automatically returns to the closed position if the reset device is kept in the reset position when the water becomes cold. 24.102 The operating temperature of the thermal circuit breaker in a closed water heater should not exceed the following recommended values: 99C; 130C140C.
Compliance is determined by inspection and Clause 24.103 or 24.104. During the test, install the water heater according to normal usage conditions, fill the container with water, and close the water outlet valve.
24.103 For temperatures of 130°C and 140°C, all thermostats used in the tests of Chapter 11 shall be short-circuited. When the water heater works until the thermal circuit breaker operates, use a thermocouple to measure the maximum temperature reached by the container; for non-metallic containers, use a thermocouple to measure the water temperature in the container.
For metal containers, fix the thermocouple on the outer surface of the upper dome. If the container is placed vertically, fix the thermocouple at half the height of the dome; if the container is placed horizontally, attach two thermocouples As shown in Figure 2-1, it is fixed on the outer surface along the maximum height line of the container.
For non-metallic containers, place the thermocouple 50mm below the upper inner surface of the container, and the lead wire of the thermocouple passes through the outlet water104-outlet diffused water heater must be able to withstand the vacuum shock that occurs during normal use. According to the requirements of 22.103, the container is evacuated to a vacuum of 33kPa without holes and maintained for 15 minutes. Compliance is determined by testing.
After the test, the container should not have any deformation that affects safety. Note: ① If there is a vacuum safety relief valve, it should work. ②The test can be carried out on a separate container. 22.105 The water inlet pipe that can transport the water in the container from the top of the container to the bottom of the container should be clamped with reliable tools so that its displacement in any direction in the horizontal plane does not exceed 6mm. GB4706.12-1995
In addition, if the water inlet pipe is made of non-metallic material, it should be able to withstand dissolution and brittleness within the normal temperature range of the water heater, and prevent deformation, breakage, bending and similar situations.
Conformity is determined by inspection and measurement. 22.106 Components that are in direct contact with the outer surface of the container should be reliably fixed to prevent loosening during normal use. Compliance is determined by inspection.
22.107 For built-in water heaters without shells, if metal mesh is used to fix the insulation material, it should be reliably fixed in place so that it should not slip due to slippage during installation, transportation and use. and distortion, thereby reducing creepage distances and clearances below the minimum allowable values ??stipulated in Article 29.1.
Conformity is determined by inspection and measurement. 22.108 Water heaters should be connected to the water supply pipes in a reliable way. Wall-mounted water heaters must have a reliable device that allows them to be fixed to the wall and easily connected to the water supply pipe. Compliance is determined by inspection or installation test. 22.109 For water heaters that cannot be drained through the drainage device in the water pipe and have a capacity greater than 15L, there should be a drain valve or a drain plug that can only be opened with a tool to make the water in the water heater easy to drain. Compliance is checked by visual inspection and manual testing. Note: ① After the water in the electric water heater is drained, a small amount of water remaining below the water source valve is allowed. ② The drain valve or drain plug can be assembled in the safety valve of the electric water heater to prevent the water heater from being damaged due to freezing and making the water heater unsafe. 23 Internal wiring
The contents of this chapter in GB4706.1-92 are applicable. 24 Components
This chapter in GB4706.1--92 is applicable except for the following content. 24.1 The following content is added to this article:
Note: The switch installed in the water heater does not need to be operated frequently. The following clauses are added to this chapter:
24.101 Thermal circuit breakers shall be of the non-automatic reset type. They shall have an automatic breaking mechanism or be positioned within a non-removable cover that can be reset only after the cover is moved.
Conformity is determined by inspection.
Note: ① "Automatic circuit breaking" means that when the water temperature in the water heater exceeds the specified limit, the thermal circuit breaker should be structured to open the contacts regardless of the position of the starting device.
② The thermal circuit breaker can be used if the contact automatically returns to the closed position if the reset device is kept in the reset position when the water becomes cold. 24.102 The operating temperature of the thermal circuit breaker in a closed water heater should not exceed the following recommended values: 99C; 130C140C.
Compliance is determined by inspection and Clause 24.103 or 24.104. During the test, install the water heater according to normal usage conditions, fill the container with water, and close the water outlet valve.
24.103 For temperatures of 130°C and 140°C, all thermostats used in the tests of Chapter 11 shall be short-circuited. When the water heater works until the thermal circuit breaker operates, use a thermocouple to measure the maximum temperature reached by the container; for non-metallic containers, use a thermocouple to measure the water temperature in the container.
For metal containers, fix the thermocouple on the outer surface of the upper dome. If the container is placed vertically, fix the thermocouple at half the height of the dome; if the container is placed horizontally, attach two thermocouples As shown in Figure 2-1, it is fixed on the outer surface along the maximum height line of the container.
For non-metallic containers, place the thermocouple 50mm below the upper inner surface of the container, and the lead wire of the thermocouple passes through the outlet water104-outlet diffused water heater must be able to withstand the vacuum shock that occurs during normal use. According to the requirements of 22.103, the container is evacuated to a vacuum of 33kPa without holes and maintained for 15 minutes. Compliance is determined by testing.
After the test, the container should not have any deformation that affects safety. Note: ① If there is a vacuum safety relief valve, it should work. ②The test can be carried out on a separate container. 22.105 The water inlet pipe that can transport the water in the container from the top of the container to the bottom of the container should be clamped with reliable tools so that its displacement in any direction in the horizontal plane does not exceed 6mm. GB4706.12-1995
In addition, if the water inlet pipe is made of non-metallic material, it should be able to withstand dissolution and brittleness within the normal temperature range of the water heater, and prevent deformation, breakage, bending and similar situations.
Conformity is determined by inspection and measurement. 22.106 Components that are in direct contact with the outer surface of the container should be reliably fixed to prevent loosening during normal use. Compliance is determined by inspection.
22.107 For built-in water heaters without shells, if metal mesh is used to fix the insulation material, it should be reliably fixed in place so that it should not slip due to slippage during installation, transportation and use. and distortion, thereby reducing the creepage distance and clearance below the minimum allowable values ??stipulated in Article 29.1.
Conformity is determined by inspection and measurement. 22.108 Water heaters should be connected to the water supply pipes in a reliable way. Wall-mounted water heaters must have a reliable device that allows them to be fixed to the wall and easily connected to the water supply pipe. Compliance is determined by inspection or installation test. 22.109 For water heaters that cannot be drained through the drainage device in the water pipe and have a capacity greater than 15L, there should be a drain valve or a drain plug that can only be opened with a tool to make the water in the water heater easy to drain. Compliance is checked by visual inspection and manual testing. Note: ① After the water in the electric water heater is drained, a small amount of water remaining below the water source valve is allowed. ② The drain valve or drain plug can be assembled in the safety valve of the electric water heater to prevent the water heater from being damaged due to freezing and making the water heater unsafe. 23 Internal wiring
The contents of this chapter in GB4706.1-92 are applicable. 24 components
This chapter in GB4706.1--92 is applicable except for the following content. 24.1 The following content is added to this article:
Note: The switch installed in the water heater does not need to be operated frequently. The following clauses are added to this chapter:
24.101 Thermal circuit breakers shall be of the non-automatic reset type. They shall have an automatic breaking mechanism or be positioned within a non-removable cover that can be reset only after the cover is moved.
Conformity is determined by inspection.
Note: ① "Automatic circuit breaking" means that when the water temperature in the water heater exceeds the specified limit, the thermal circuit breaker should be structured to open the contacts regardless of the position of the starting device.
② The thermal circuit breaker can be used if the contact automatically returns to the closed position if the reset device is kept in the reset position when the water becomes cold. 24.102 The operating temperature of the thermal circuit breaker in a closed water heater should not exceed the following recommended values: 99C; 130C140C.
Compliance is determined by inspection and Clause 24.103 or 24.104. During the test, install the water heater according to normal usage conditions, fill the container with water, and close the water outlet valve.
24.103 For temperatures of 130°C and 140°C, all thermostats used in the tests of Chapter 11 shall be short-circuited. When the water heater works until the thermal circuit breaker operates, use a thermocouple to measure the maximum temperature reached by the container; for non-metallic containers, use a thermocouple to measure the water temperature in the container.
For metal containers, fix the thermocouple on the outer surface of the upper dome. If the container is placed vertically, fix the thermocouple at half the height of the dome; if the container is placed horizontally, attach two thermocouples As shown in Figure 2-1, it is fixed on the outer surface along the maximum height line of the container.
For non-metallic containers, place the thermocouple 50mm below the upper inner surface of the container, and the lead wire of the thermocouple passes through the outlet water
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